This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Extensive research on SERMS has been performend in humans, but not specifically to examine estrogen receptor activity in skeletal muscle. Limited studies investigating the effects of hormon replacement therapy and physical activity on skeletal muscle strength gains in women have been conducted while no studies investigating estrogen receptor activity in skeletal muscle with eccentric resistance training as a stimuls in women using SERMs have been reported. We will analyze estrogen receptor modulator gene expression in skeletal muscle tissue in women after a high intensity, eccentric resistance training protocol and evaluate the changes in CK and TNF-a to assess the magnitude of muscle damage.